Fish curing apparatus



July 17, 1951 A. J.'W|L.SON

FISH CURING APPARATUS 3 Sheets-Sheet 1 Filed Feb. 12, 1949 F IG.I.

Inventor HUEXRNDER W\ LSON y 1951 A. J. WILSON 2,560,677

FISH CURING APPARATUS Filed Feb. 12, 1949 3 Sheets-Sheet 2 Inventor HLEXRNDER MANSON JAM-6 J y 17, 1951 v A. 4. WILS'ON 256mm FISH CURING APPARATUS Filed Feb. 12, 1949 Y 5 Sheets-Sheet 5 Attorney Patented July 17, 1951 FISH CURING APPARATUS Alexander John Wilson, Aberdeen, Scotland, as-

signor of one-half to Thomas Adam, Aberdeen,

Scotland Application February 12, 1949, Serial No. 76,169 In Great Britain September 2, 1948 Claims.

This invention has for its object to provide an improved apparatus for producing and controlling the smoke for curing fish and other foodstuffs, and to an improved method, whereby the curing is effected in a simple, economical, efficient and expeditious manner.

The invention consists in an apparatus comprising a curing chamber, a furnace having an outlet flue in communication with an inlet port in the lower part of the curing chamber, a rotary fan or exhauster for drawing smoke from the furnace and charging the curing chamber with smoke when the said inlet port is open, and a controlled communication between the furnace and the curing chamber for by-passing the smoke to an escape vent and for admitting air to the curing chamber. I

The invention further consists in drawing smoke or hot air from the furnace into and through the curing chamber by connecting the fan or exhauster to an outlet port in the curing chamber. Alternatively, the fan or exhaustcr is located between the curing chamber and the furnace.

The invention also consists in an apparatus comprising a curing chamber, a furnace having an outlet flue in communication with an inlet port in the lower part of the curing chamber, a rotary fan in the outlet flue, valve-controlled air inlet and smoke outlet ports in the flue between the furnace and the fan, and an exhaust fan in communication with an outlet port in the curing chamber. The exhaust fan may also communicate with the valve-controlled smoke outlet port.

The invention also consists in the provision, within the furnace, of one or more electric heating elements for igniting saw dust, wood shavings, or like wood fuel for the production of the smoke.

The apparatus may accordingly comprisea curing chamber, a furnace having means for chargin it with saw dust, wood shavings or other small Wood fuel, an electric heating element in the furnace for igniting the wood fuel, an exhauster for drawing smoke from the furnace and for supplying the curing chamber with smoke through an inlet port, and means for controlling the admission of smoke and/or air to the curing chamber through the said inlet port.

The invention also consists in an improved method of curin fish or other foodstuffs in' a curing chamber which is in communication with a furnace having one or more electric heating elements therein, which comprises first circulating hot air through the curing chamber from the furnace, then igniting wood fuel in the furnace and charging the curing chamber with smoke from the furnace, and thereafter circuz lating smoke from the furnace through and out of the curing chamber to effect final curing.

An embodiment of a fish curing apparatus according to the invention is illustrated in the accompanyng drawings in which Fig. 1 is a side view of the apparatus. Figs. 2 and 3 are detail views of the valve-controlled smoke and air passages to the curing chamber. Fig. 4 is a front view of the apparatus, and Fig. 5 is a side View seen from the opposite side to that in Fig. 1.

The apparatus comprises a curing chamber I having a front door 2 and fitted internally with racks or rails (not shown) for the suspension of the fish or other food to be cured. The chamber l is mounted above a furnace 3 provided with a charging door 4 for charging the furnace with saw dust or small wood fuel which is ignited on the grate by means of electric heating elements 5. A rake is indicated at 6 and an ash-pan at I. It is preferred to provide an air space 8 between the top of the furnace and the underside of the curing chamber to prevent over-heatin of the bottom plate of the curing chamber which is conveniently made of metal. The curing chamber may be placed in any convenient position relatively to the furnace.

Valve-controlled communication between the furnace and the curing chamber is provided by an induction box 9 which communicates with an outlet in the upper part of the furnace and with the casing ID of a fan II which discharges through a port [2 opening into the lower part of the curing chamber. A smoke diffuser indicated in broken lines at l3 may be fitted in the lower part of the curing chamber. 1 The induction box 9 has a smoke vent pipe it. connected thereto and has an atmospheric air inlet opening 15, both controlled by a duplex valve comprisin valve members It and I1 connected together by one or more connecting bars I8 and pivoted on a spindle IS. A handle 20 pivoted to the valve member It enables the duplex valve to be opened and closed, and in the closed position the handle 20 can be engaged with a catch 2|. Fig. 2 shows the duplex valve in the closed position in which smoke passes from the furnace to the curing chamber as indicated by the arrows. Fig. 3 shows the duplex valve fully open, when the smoke passes from the furnace to the smoke vent pipe I4 and atmospheric air enters the induction box and passes to the curing chamber as shown by the arrows. It will be apparent that the fan It can draw smoke or hot air from the furnace and deliver it to the curing chamber when the duplex valve is open as shown in Fig. 2. When the duplex valve is closed as in Fig. 3, the fan it may draw in atmospheric air and deliver it to the curing chamber, and if the duplex valve is partly open, the fan II will deliver a mixture of smoke and air to the curing chamber.

The fan II is driven by an electric motor 22 and a switch board 23 is provided to control the connections leading therefrom to the motor 22 and to the electric heating elements 5.

The smoke vent pipe I 4 may open into a chimney, but it is preferred to connect it to the suction side of an exhaust fan 24 which is mounted on the top of the curing chamber and is connected to a suction pipe 25 which forms an outlet from the curing chamber. The exhaust fan 24 is driven by an electric motor 26.

In operation, the action of the improved apparatus for curing fish is as follows:

The pickled fish is suspended on the racks or rails in the curing chamber and the door 2 is closed. The electric heating elements and exhaust fan motor 26 are then switched on, drawing hot air from the furnace through the curing chamber to crystallize the pickle and partially dry the fish. This may be continued for say one hour. The exhaust fan motor 26 is then switched off and a little sawdust is sprinkled over the furnace grate. When this has become ignited, the electric heating elements may be switched off. The lower fan I l is then set in operation and additional sawdust fed to the furnace as required in order to charge the curing chamber with smoke. This may be continued for say 30 minutes. The motor of the lower fan H is then switched off and the exhaust fan 24 is set in operation to circulate smoke through the curing chamber for a period of say one hour or longer according to the degree of colouring desired.

The volume and velocity of the smoke .and hot air or of smoke admixed with cold air can be regulated by adjustment of the duplex valve in the induction box 9. Humidity in the curing chamber is greatly lessened, because the bulk of the air passing into the curing chamber is dried whilst being drawn through the furnace.

From the foregoing description it will be understood that the method of curing consists in first forcing the smoke into the curing chamber to impregnate and color the fish, then to change over to suction or extraction, still drawing smoke from the furnace into the curing .chamber.

When it is desired to inspect the curing or to remove the cured fish, the duplex valve in the induction box 9 can be fully opened, as shown in Fig. 3, without the smoke escaping through the open door of the curing chamber.

I claim:

1. Apparatus for curing fish or other foodstuffs comprising a curing chamber having an inlet port in the lower part thereof, a smoke-producing furnace beneath said chamber, a controlled communication between said inlet port and said furnace, and exhauster for drawin smoke from said furnace and for charging said chamber with smoke, and a pair of interconnected valves controlling smoke escape and air inlet ports respectively located in said communication and means for operating said valves in unison to open one of said K valves while closing the other of said valves.

2. Apparatus as specified in claim 1 including an exhaust outlet duct connecting said exhauster to said curing chamber and located between said controlled communication and the inlet port in said curing chamber.

3. Apparatus fOr curing fish or other foodstuffs comprising a curing chamber havin an inlet port in th lower part thereof, a smokeproducing furnace, a duct connecting said inlet port to said furnace, a rotary fan in said duct adjacent said inlet port, air inlet and smoke outlet ports in said duct between said fan and said furnace, an exhaust fan in communication with said curing chamber, a smoke duct connecting said smoke outlet to said exhaust fan, a valve controlling said air inlet port, a valve controlling said outlet port, andmeans operatively interconnecting said valves to open one of said valves while the other is being closed.

4. Apparatus for curing fish or other foodstuffs comprising a curing chamber, a furnace having means for charging it with small wood fuel, a furnace grate, an electric heating element horizontally disposed adjacent said grate for igniting the fuel thereon, an exhauster for drawing smoke from said furnace and for charging said chamber with smoke, an air inlet to said exhauster, a by-pass passage for smoke from said furnace, a valve controlling said air inlet and arranged to prevent the passage of smoke to said exhaust when said air inlet is fully opened by said valve, a valve controlling said by-pass passage, and means for simultaneously operating said valves to simultaneously open or close the air inlet and by-pass passage.

5. Apparatus for curing fish or other foodstuffs comprising a metallic casing forming a curing chamber, a door giving access to said chamber, a smoke-producing furnace located beneath said casing and spaced therefrom to provide an air space between the top .of said furnace and the underside of said casing, a duct connecting said furnace to an inlet port in the lower part of said curing chamber, a rotary blower in said duct, an atmospheric air inlet port and a smoke outlet port in said duct at the furnace side of said blower, an electrically-heated fuel igniting element in said furnace, an extractor fan in communication with the upper part of said chamber through an exhaust duct, an auxiliary smoke duct connecting said smoke outlet port with said exhaust duct, means for driving said blower and extractor fan independently to cause hot air or smoke to be drawn into said chamber from said furnace when said extractor fan is in operation, and to cause smoke with or without admixture with atmospheric air to be forced into said chamber when said blower is in operation, a valve controlling said air inlet port and arranged when open to obstruct passage of smoke from said furnace to said blower, a valve controlling said smoke outlet port and arranged when open to obstruct passage of smoke from said furnace to said blower, means interconnecting said valves in such relationship that both valve open together and close together, and means for operating said valves.

ALEXANDER JOHN WILSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

